Furnace and stoker



Sept. 9, 1941. v. c. KLINE 2,255,171

FURNACE AND STOKER Filed April 28, 1936 5 Sheets-Sheet l INVENTOR Sept.9, 1941;

v. c. KLINE FURNACE AND STOKER s Sheets-Sheet 2 Filed April 28, 1936 5 52 1 I VVVV LL 4 F I) 5 2 2 3 5 E H 3 M 9 u m tl3 .6 B Q G 9 0 w w 2 0 w3 a 4 2 8 FIG. 5.

I INVENTOR Sept. 9, 1 941. v. c. KLINE 2,255,171

FURNACE AND STOKER Filed April\ 28, 1936 3 Sheets-Sheet 3 FIG."

as zsz 75 INVENTOR Patented Sept. 9, 1941 UNETED STT- FHE 14 Claims.

This invention relates to a new furnace and stoker for consuming solidcomminuted fuel, the invention being particularly applicable to domestichousehold heating furnaces.

It is the primary object of the invention to provide, in a device ofthis character, an underfeed stoker which will supply the requiredamount of fuel and maintain it properly distributed around the furnacewith sufficient agitation to prevent excessive clinker formation.

It is a further object to maintain the fuel bed adjacent the outer wallsof the furnace for securing increased efficiency from the apparatus.

Referring to the drawings wherein I have shown the preferred embodimentsof my invention,

Fig. 1 is an elevational view of one form of apparatus constructed inaccordance with the present invention,

Fig. 2 is a horizontal view thereof, partly in section, taken on theline 22 of Fig. 1,

Fig. 3 is a vertical sectional view taken on the line 33 of Fig. 2, i

Fig. 4 is an enlarged fragmentary view of the base plate of the fire potshowing the distributor rin in position,

Fig. 5 is a sectional view thereof taken on the line 55 of Fig. 4, V

Fig. 6 is a bottom plan view of the distributor ring shown in Figs. 4and 5,

Fig. '7 is a view similar to Fig. 2 showing a modification of myinvention,

Fig. 8 is a vertical sectional view of the line 8-8 of Fig. 7,

Fig 9 is an enlarged cross-sectional view of the fuel-feeding devicetaken on the line 9-9 of Fig. '7,

Fig. 10 is a longitudinal section taken on the line |0l0 of Fig. 9, and

Fig. 11 is an enlarged fragmentary transverse sectional view of thedevices for moving the distributing ring, shown in Fig. 7. g

In the first form of the invention, the furnace I is a typical domesticboiler furnace, having a water-jacketed section 2 and a supporting base3. The furnace has a usual fuel door 4, a clinker doorway at 5, and anash pit doorway at 6. In place of the usual grates, I provideafuel-supporting frame comprising a base plate 8 and an upstandingportion 9, forming in the embodiment shown a frustrum of a cone at thecenter of the furnace. The base plate 8 preferably extends outwardlyunder the side wall 2 of the furnace. The upstanding portion 9 may forma continuation of the base plate or be separately l8 of the ash conveyor20.

formed and secured upon the base plate, as will be understood.Theportions 8 and 9 together with the side wall 2 form a fire pot ID,the portion 9 being formed with a number of air passages ea foradmitting air to the fuel in the fire pot.

The upstanding wall 9 may be protected by removable perforated .platesll, constructed of metal, tile or the like, bolted or otherwise held inposition thereon. The upper edge of the portion 9 is covered by one ormore rings 12, formed with air passages [3 leading outwardly from thespace within the wall 9 to the fire pot. A cap plate l4, which may be ofsuificient weight to maintain the rings in position, or else bolted tosaid rings, is mounted above rings l2.

The cap plate l4 and rings'IZ form a central opening through which ashdischarges into passage l5 formed by pipe Hi leading to the passage Thisconveyor is shown as a typical screw conveyor for removing ash from thespace beneath the passage 15 and discharging the same outside of thefurnace into a container (not shown).

The base plate 8 may be formed with a series- 1 form of the invention,is particularly constructed to admit a certainamount of air from theopenings 22 into the fuel bed and to distribute fuel around the fuelpocket when the stoker is in operation.

Referring to Figs. 4, 5 and 6, the ring 24 is formed on its lowerfacewith a circular groove 25 entirely encircling the ring. Inclinedtransverse slots extend from the central groove 25 to the outer edgeofthe ring to provide air ducts leading from the passages 22 to the spacewithin the fire pot. In the first form of the invention the uppersurface of the ring is formed with a succession of thumb slots 26 on theupper edge thereof constructed to be engaged by a suitable plunger formoving the ring. The inner reduced edge 28 of the ring extends beneaththe flanged edges of securing lugs 30, bolted to the base plate 8. Thelugs 39 form anti-friction bearings for maintaining the ring 24 inposition and for preventing its upward displacement during operation ofthe stoker.

During movement of the ring 2 3, fuel is distributed about the annularfire pot by means of projecting fingers 32 mounted onthe ring 24, andextending upwardly and 'rearwardly withrespect to the movements of thering, whereby the fuel is periodically lifted and agitated anddistributed around the fuel pocket as the ring is moved. One or moredistributing fingers 32 may be employed.

Fuel may conveniently be supplied to the fire pot shown in the'firstform of the invention by removing the clinker door and placing in itslocation a plate 34 having a central sleeved portion 35, forming anopening for receiving the fuel feeding pipe 35. The fuel supply pipe 36,secured within the sleeve 35, is preferably inclined slightly as shownand directed over the thumb slots 26 in the ring 24. Fuel is supplied tothe pipe 36 through the opening 31 opening into the lower portion of thefuel hopper 38. A plunger 40 slides within the pipe 36, from a positionnear its open end to a point beneath the opening 31, the extent to whichthe plunger 45 exposes the opening 3'! determining the quantity of fueladded at each stroke. The plunger 40 may be connected byan adjustablelink 42 to an eccentric 44 mounted on the vertical drive shaft 45connected by suitable reduction gearing to the motor 45. At the forwardend of the plunger do, there is mounted a push bar 48 rigidly secured tothe plunger 48 and positioned to engage within the thumb slots 26 in thering 24 as the plunger moves forward. During rearward movements of theplunger 40, the bar 48 is retracted into position to become engaged withother thumb slots during the next forward movements of the plunger. Dueto the slight inclination of the tube 36 and plunger 40, as shown inFig. 1, the bar 48 may be retracted entirely out of contact with thering 24 and be brought into engagement with one of the thumb slots onlyduring a portion of its next forward movement, thereby moving the ringto the extent of only one or two slots. In this way, the ring 24 ismoved to a lesser extent than the total movement of the plunger 40. Ifdesired, a suitable guide for the bar 48 may be provided adjacent theupper edge of ring 24 to assure contact of the bar in the slots 26 andto raise the plunger to prevent it from unintentionally contacting slots25 when in its fully withdrawn position, thus making certain that theplunger will move the ring one or more slots, as desired.

A forced draft of air is supplied by means of a blower 59 which may bemounted directly on the shaft of motor 45. The blower directs airthrough the conduit 52 from which the air passes through a duct 53leading directly to the base of the upstanding wall 9 of the fire pot.Air is thus discharged outwardly through the openings in wall 9 into thebody of fuel being consumed. A certain proportion of the air may beadmitted directly to the ash pit, if desired, through the opening 54controlled by the slide valve 55. The division of the air between theash pit and passage leading directly to the air openings 9a is notessential as the furnace will operate satisfactorily with air suppliedonly to the openings 9a or with duct 53 omitted and air supplied only tothe ash pit space.

It will be noted that in general the draft applied tothe fuel in thefurnace is outwardly toward the side wall of the boiler to be heated.This is a desirable feature of the invention. Under some conditionsadditional combustion promoting air is desirable above the bed of fire.For this purpose one or more jet pipes 56 may be employed with airnozzles directed toward the side wall of the furnace. The air suppliedfrom the pipes 56 serves not only to direct the flames against the sidewalls but also create a vortex behind the pipes for causing any smallparticles of ash escaping with the flames to fall into the dischargepassage at the center of the furnace.

In the form of the invention shown in Figs. 7 to 11, the same generaltype of furnace and stoker is disclosed, except that the fuel issupplied beneath one side of the fire pot and forced up into the samefrom beneath. This permits introduction of the fuel through the ash pitdoor space. To this end, the plate 51 forming the base of the fire potis formed with an opening 58 adjacent the outer edge of the plate. Aconduit 59 is placed beneath the opening 58 for directing fuel upwardlythrough the opening, the conduit being formed with a sleeve 60 forreceiving the fuel pipe 5!, extending to a point without the furnace.The fuel pipe 6| is formed with an opening Bia for receiving fuel fromthe hopper.

Fuel received within the pipe (ii is advanced in any preferred manner.The devices shown for this purpose include a small steel bar 62extending through the length of the tube and connected to an operatinglever 63, pivoted at 54, and connected-by link 65 to an eccentric 66driven from a suitable motor, as in Fig. l. A series of advancing lugs51, carried by the bar 62, are formed with inclined upper surfaces 68and advancing edges 89, for advancing fuel through the tube on forwardmovement of the bar. The lugs 61 may be suitably curved on their lowersupporting edges, as shown at E5, to conform to the interior curvatureof the tube 6|. The lugs 6'! may be secured individually on the shaft 52although it is sufficient to employ keys T2 at the forward and rearwardends of the series of lugs to secure the lugs on the bar.

In this second form of the invention, a different type of advancing ring14 is. employed. This ring may be in the form of a T iron, the base ofwhich extends downwardly through a circular opening it formed in thebase plate 51. The plate in this case is reinforced by cross brackets l8suitably placed around the plate 5'! and spanning the circular openingI6. The ring 14 is provided with projecting fingers. so that when thering is rota-ted fuel is agitated and advanced around the fire pot. Inthe form of the invention shown the ring M is advanced by means of aconstruction embodying anadvancing lug 82 formed with jaws 84 whichclamp the base 15 of the circular T bar when the lu 8-2 is advanced. Thelug 82 is pivotally connected to a yoke 86 carried by an operating link88, in turn connected to the rearward end of lever 63 beyond its pivot64. The lug 82 is formed with a projecting end 63 which engages the baseof the yoke 85 duringrearward movement of the link 88, so that therearward movement of the link 88 does not move the ring I4. Duringforward movement of the link 88 and lug'82, the jaws 84 bind upon thebase 15 'of the ring M and advance it to a small extent during eachrearward movement of the fuelfeeding bar 62.

It will be understood that the constructions disclosed herein are by wayof illustration only and that modifications thereof may be made so longas they fall within the scope of the appended claims.

Z-Iaving now described my invention, I claim:

1. In a furnace, an annular fire pot therein and an ash dischargeopening, an underfeed stoker for supplying fuel to the lower portion ofsaid fire pot, movable means within said fire pot for evenlydistributing fuel around the same and for agitating successive portionsof said fuel periodically during normal operation of said stoker.

2. In combination with a furnace having a fire pot, underfeed stokermechanism for feeding fuel into one side of said fire pot, a movabledistributor for moving and distributing said fuel circumferentiallyaround said fire pot, means for supplying a forced air draft into saidfuel and means for discharging ash from said fire pot.

3. In combination witha furnace having a combllstion chamber, an annularfire pot therein, a fuel feeding device for introducing fuel into saidfire pot beneath the upper surface of the fuel therein, a member movablecircumferentially around said annular fire pot for distributing fueltherein, means for advancing said movable member by a step by stepmovement and means for supplying combustion promoting air to the fuel insaid fire pot.

4. In combination with a furnace having an annular fire pot and sidewalls, a fuel feeding device for introducing fuel into said fire pot,means for supplying combustion promoting air to the fuel in said firepot and means for directing an additional draft of combustion promotingair over the fuel in said fire pot outwardly toward the side walls ofsaid furnace.

5. In combination with a furnace, a fuel support comprising an annularfire pot within said furnace, means for introducing solid fuel into oneportion of said fire pot beneath the fuel therein and rotatably movablemeans for distributing said fuel substantially uniformly around saidfire not from the place of introduction.

6. In a furnace, a fire pot having an annular base and formed with anupwardly projecting central ash discharge outlet duct, means forintroducing fuel into the lower portion of said fire pot, and amechanical fuel distributing member supported for movement over the baseof said fire pot for distributing fuel therein.

7. In a fuel supply device for furnaces, a fuel support, a hollowupstanding member of frustoconical form positioned centrally of saidsupport and including a central ash discharge outlet, means forintroducing fuel onto said support below the level obtained by the fuelduring operation of the device, and mechanical means movable around saidupstanding member for evenly distributing said fuel about said supportduring said operation.

8. In combination with a furnace having a combustion chamber, a fire pottherein having an annular base, a feeding device for introducing fuelinto the lower portion of said fire pot, an annular distributing ringsupported on said base, fuel distributing members carried by said ring,means for moving said ring circumferentially around said fire pot fordistributing and agitating the fuel therein and means for supplyingcombustion promoting air to the fuel in said fire pot.

9. In a furnace, an annular fire pot having a central ash dischargeopening, means for introducing fuel into the lower portion of said firepot, an annular distributing member rotatably mounted on the base of andlocated within said fire pot and including fuel distributing elements,

'combustion chamber, a base plate and an upstanding hollow central wallforming with the outer wall of said furnace an annular fire pot at thebase of said combustion chamber, a fuel feeding device for introducingfuel into said fire pot, means for supplying combustion promoting airunder forced draft directly to the inner margin of said fire pot alongsaid central upstanding wall and at the upper edge thereof, and meansfor supplying additional combustion promoting air at points remote fromthe inner margin of said fire pot including means for directing a draftof combustion promoting air over the fuel'in the fire pot and outwardlytoward the outer wall of the furnace.

11. In a furnace, a fire pot having an annular base and a centraloverflow ash discharge outlet, means for supplying fuel into the lowerportion of the fire pot, an annular ring supported on said base, fueldistributing means carried by said annular ring, and means operating inconjunction with said fuel supplying means for intermittently movingsaid annular ring.

12. In a furnace, a fire pot having an annular base and a centraloverflow ash discharge outlet, means for supplying fuel into the lowerportion of the fire pot, an annular ring supported on said base, fueldistributing means carried by said annular ring, and reciprocable meansoperated from said fuel supplying means for imparting a step by steprotating movement to said annular ring.

13. In a furnace, a fire pot having an annular base and a centraloverflow ash discharge outlet, means for supplying fuel into the lowerportion of the fire pot, an annular fuel distributing ring supported onsaid base, reciprocable means operated from said fuel supplying meansand supported and arranged to contact said ring to impart movementthereto upon forward movements of the reciprocable means and to be outof operative engagement with the annular ring on rearward movements ofthe reciprocable means.

14. In a furnace, a fire pot having an annular base and acentraloverflow ash discharge outlet, means for supplying fuel into the lowerportion of the fire pot from below the base thereof, a

fuel distributing annular ring supported on said base and including aportion extending through said base, and reciprocable means operating inconjunction with said fuel supplying means and arranged to be inoperative relationship to said extending portion of said ring uponforward movements of. the reciprocating means to rotatably move saidring, and to be out of operative relationship to said extending portionupon rearward movements of said reciprocating means.

VIRGIL C. KLINE.

